SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3605697b2b76df57f48b19bc5d04f8d3de2828dd6f59737f74b3cf1b9df449a9' 
  AND token = 'AN+VfbsXhkJ0x0w1O8nG6Aap4lVMQ+HoLphFgx1zyV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}